1. Field of the Invention
The present invention relates to the field of a battery tester and, more particularly, to a battery tester with high precision.
2. Description of Related Art
There are many types of the rechargeable battery with different capacities in the market. The battery tester is used to detect the residual capacity of the rechargeable battery and determine the health of the rechargeable battery. However, the conventional battery tester uses only one method to detect different rechargeable batteries, and consequently, inaccurate testing result will likely occur.
In general, the conventional battery tester uses ½ cold cranking amps (hereinafter CCA) testing method that utilizes half of the battery capacity to detect the health of the rechargeable battery, the method having steps of: (a) adding a load to the two electrodes of the battery to discharge the battery by loading the amperes of ½CCA for 15 seconds; and (b) determining the health of the battery according to the discharging diagram.
In the conventional testing method implemented by the battery tester, the resistance of the load and the duration of adding load to the battery are fixed. Under the circumstance of fixed load resistance and loading duration, when such battery tester is used to detect rechargeable batteries with different capacities, imprecise testing results from the discharging diagrams inevitably arise. The testing precision of the conventional battery tester is not ideal for all rechargeable batteries.
To overcome the shortcomings, the present invention provides a battery tester with high precision to mitigate or obviate the aforementioned problems.